tests/test-hup.t

extdiff: drop the command alias without options example in the help text

In the dropped example, the extension would look for 'vdiff.diffargs' in the
configuration, and not finding it, would run kdiff3 without the configured
options.  That's not obvious to a new user who sees a kdiff3 configuration in
the prepackaged mergetools.rc file, and sees that kdiff3 still runs.  While it
is conceivable that the user wants a kdiff3 command that runs without the
preconfigured options, it is more likely what they want is this, which uses the
canned options:

    [alias]
    vdiff = kdiff3

    [extdiff]
    kdiff3 =

We could mention alias here, but that seems like it belongs elswhere.

#require serve fifo

Test hangup signal in the middle of transaction

  $ hg init
  $ mkfifo p
  $ hg serve --stdio < p 1>out 2>&1 &
  $ P=$!

Do test while holding fifo open

  $ (
  > echo lock
  > echo addchangegroup
  > start=`date +%s`
  > # 10 second seems much enough to let the server catch up
  > deadline=`expr $start + 10`
  > while [ ! -s .hg/store/journal ]; do
  >     sleep 0;
  >     if [ `date +%s` -gt $deadline ]; then
  >         echo "transaction did not start after 10 seconds" >&2;
  >         exit 1;
  >     fi
  > done
  > kill -HUP $P
  > ) > p

  $ wait
  $ cat out
  0
  0
  adding changesets
  transaction abort!
  rollback completed
  killed!

  $ echo .hg/* .hg/store/*
  .hg/00changelog.i .hg/journal.bookmarks .hg/journal.branch .hg/journal.desc .hg/journal.dirstate .hg/requires .hg/store .hg/store/00changelog.i .hg/store/00changelog.i.a .hg/store/journal.phaseroots